Fig. 1. (Color online) Interface energetics in PSCs. (a) Device structure of PSCs. (b) Underlying electrode dependent perovskite surface energetics. (c) Constructing perovskite p−n (n−p) homojunction for p−i−n (n−i−p) PSCs.

Fig. 2. (Color online) Interface energetics in OSCs. (a) Device structure of OSC with a LbL- or BHJ-type PAL. (b) ETL and HTL downshifting and upshifting WF, respectively, of metallic contacts to align with PAL quasi Fermi level of the appropriate majority carrier.